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Improving Working Conditions
in the RMG Sector
Common Standard
Guidelines for Structural
Safety Assessment of RMG
Buildings in Bangladesh
Professor Dr. Ahsanul Kabir
CE Dept., BUET, Dhaka
Safety Assessment Stages
Stage 1: Preliminary visual inspection(based on visual observation of distress and some rudimentary calculation)
Stage 2: Detail engineering investigation (based on field and laboratory testing
followed by analysis and design checking)
Stage 3: Design of Retrofit Scheme(based on stage 2 findings)
Visual Inspection (Stage-1)
ESTABLISH AIMS AND REQUIREMENTS
DOCUMENT SURVEY
SITE VISIT FOR VISUAL INSPECTION & INFORMATION
COLLECTION
STA
GE
1
PRELIMINARY CALCULATION OF CAPACITY
REPORTINGCheck if detail analysis
is reqd.? If yes stage 2 reqd.
Structural Assessment is a process to evaluate
the existing structure in terms of withstanding
the current loads to which it is subjected and
probable loads that it is going to experience in
future time :
Need for Common Guidelines
• Assessment of Existing Building is
different from design of a new building
• Assessment depends on Engineering
judgment of person/s and experience
Need for Common Guidelines (p/2)
• Compliance to Building code may not
be met, yet the building can serve the
present purpose with low risk
• Different groups may differ in their
opinions regarding safety
• A common guideline and a central
body is essential to remove the
differences
• Methods for Design Adequacy
Assessment
• Safety of Foundations and Pile
Supported Structures
• Safety of RC Structures
• Loading, Load Combination and
Restricted Reduced Loading
Live Load and Lateral Loads, Load
Combinations, Prescribe Reduced Loads
• Assessment of Material Strength
Assessment Guidelines
• Durability and Maintenanceefflorescence and dampness; Water logging
• Additions and Alterations May be allowed if comply with BNBC.
• Equipment and FixturesAll non-structural elements suspended from, attached to, or resting
atop the structure shall be anchored and braced to resist earthquake
forces.
• Vulnerable/Critical MembersSlender Columns, flat plates and footings with inadequate thickness for
shear etc. are Vulnerable Critical Members
Distressed Members
Assessment Guidelines (p/2)
• Certification after Retrofitting
• Further Construction
• New Construction of RMG Factory
• Other Brand/Buyer Requirements *
• Structures with no Proper
Documentation
* To be allowed by the national committee
Assessment Guidelines (p/3)
Qualification of Engineering Team who canMake Assessment and Provide Certification
At least two qualified Engineers (one structural and
other geotechnical engineer). Minimum qualification
reqd. for applying for registration as a team:
• B. Sc Engg. (Civil or Civil and Structural or Civil and
Geotechnical) from a recognized university
• IEB Member/Fellow
• More than 10 years of Professional Experience
• Practicing as a Structural/Geotechnical Engineer or
worked in consulting company/ institution.
Registration renewable every 3 years
Assessment Guidelines (p/4)
Visual Assessment to suggest 2nd stage
Assessment Guidelines (p/5)
1. Is the structure properly designed by
professionals?Yes/No
If all these
answers are yes,
Preliminary
Assessment may
suffice. Detail
Engg Assessment
necessary, if
gross
inadequacies
exist; building
may remain
operational.
2. Is the structure free from any visible distress
(progressive cracking) in main load carrying
members?
Yes/No
3. Is the foundation adequate (in bearing and
settlement) considering the sub soil condition?Yes/No
4. Is the structure out of risk due to presence of
critical structural element (slender column, flat
plate, transfer girder, foundation weakness)?
Yes/No
5. Is the vertical and lateral load resisting system
(load path) apparently adequate?Yes/No
6. Is the structure free from cracks in column
and/or beam indicating foundation yielding?Yes/No
7. Was the building had minimum standard of civil
work supervision during construction?
Yes/No
/Uncertain
References:
1. Bangladesh National Building Code (BNBC), 2006,
2. ACI 437R-03, Strength Evaluation of Existing
Buildings.
3. ASTM 2018, Standard Guide for Property
Condition Assessments:
4. ACI 201.1R-08 Guide for Conducting Visual
Inspection of Concrete in Service.
5. ACI 318-11, Building Code Requirements for
Structural Concrete.
Assessment Guidelines (p/6)